Non-oxide selectively porous materials

ABSTRACT

A process for providing pores in a structure and a structure according to any selected physical characteristics. Generally pins or pore forming members may be positioned in a laminate preform and the laminate preform formed into a laminate structure including the pins therein. The pins generally include a size, density, distribution, angle, or other characteristic that is desired in the final laminate structure. After the laminate is formed the pins are then removed from the laminate according to a process which does not harm selected physical characteristics of the laminate structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.10/624,905 filed on Jul. 22, 2003 issued as U.S. Pat. No. 7,332,116 onFeb. 19, 2008. The disclosure of the above application is incorporatedherein by reference.

FIELD

The present invention relates generally to forming porous materials, andparticularly to methods of forming selectively porous laminatematerials.

BACKGROUND

Many materials are known to be porous, generally being naturally porous.The naturally porous materials can be provided as filters or astranspiration coolers for various applications. Nevertheless, manynatural materials include porosity that is also substantially “natural”.Simply, the natural porosity of many materials is highly variable.Although porosity for various materials may be within a selected range,the porosity can be unevenly distributed throughout the material.Moreover, the natural porosity of a selected material may be within anextreme of a range rather than within a narrow porosity range.

Nevertheless, it is desirable to provide materials that include aselected porosity. Generally these materials will include a porositythat is substantially consistent throughout the material such thatnatural variations do not occur within the material or areinconsequential relative to the selected porosity. Therefore, theporosity will include a selected porosity and pore size. The entirematerial will have known physical characteristics and can be applied ina substantially consistent manner.

Moreover, most often porous materials include a substantiallymulti-directional porosity. That is, the porosity is distributed suchthat materials may move through the pores in multiple directions, from afirst side to a second side and from the second side to the first sideof the material as well as parallel to both sides. If the porousmaterial is provided as a filter or membrane, then a pressuredifferential across the membrane must be relied upon to move thematerial in a selected direction. Generally, this requires includingadditional manufacturing steps or structural elements in the finalstructure or device.

Therefore, it would be desirable to provide a material that issubstantially directionally porous. More specifically, it would bedesirable to provide a material having a porosity that allows materialto flow along one direction relative to the porous material surfaces.The flow may be dependent upon the material in which the pores are madeor the material being flowed across the membrane. Nevertheless, themembrane is substantially uni-directional in its porosity for selectedflowable materials.

It is also desired to provide many materials including selectedporosities. That is, materials of various types including a selectedporosity that includes a selected pore density, selected pore size, andselected directional porosity. Therefore, rather than providing only asingle material including a selected porosity with a general technique,the materials could be varied and used in many different applicationsincluding different strengths and weight requirements.

SUMMARY

The invention provides a system for providing pores in a structureaccording to selected properties. Generally a structure, such as alaminate, may be formed with a selected pore according to a selectedporosity or other physical attributes. The porosity may be formed bypositioning pins or a pore forming member through a laminate preformbefore the preform is laminated to form the laminate structure. Afterforming the laminate structure the pins can be removed according tovarious processes which do not harm the physical characteristics of thelaminate structure. Therefore, the porosity of the final laminatematerial is provided according to a selected size, direction, andporosity rather than being generally random according to a naturalprocess.

According to a first embodiment of the invention a method of forming apore in a laminated material is disclosed. The method includes forming alaminate preform including a plurality of layers of material. A memberis disposed at least partially through the laminate preform. Thelaminate preform may be processed to form a substantially laminatedstructure. The member is removed from the laminated structure. Removingthe member is accomplished with substantially little oxidation andleaves a pore having at least one of desired shape and size.

According to a second embodiment of the present invention a method forforming a laminate material including a selected pore is disclosed. Themethod includes selecting a substantially oxide-free fabric and forminga fabric stack including at least one layer of the selectedsubstantially oxide-free fabric to be laminated into a substantiallycoherent laminate structure. A pin is placed into the fabric stack andthen the fabric stack is laminated such that the fabric stack becomeslaminated into a laminated structure. The pin is then removed from thelaminated structure to form a substantially selected pore in thelaminated structure.

According to a third embodiment of the present invention a high strengthpanel providing a desired degree of porosity is disclosed. The highstrength panel includes a laminated substrate including a plurality ofindependent layers of material placed adjacent one another. The panelfurther includes a plurality of pores formed in the laminated substrateby the placement of a plurality of pore forming members in at least aselected one of the plurality of independent layers of material prior toforming the laminated substrate. The plurality of pore forming membersis held in the selected plurality of independent layers of materialuntil the laminated substrate is fully formed and then removed from thelaminated substrate to form the pores.

According to various embodiments, a construct providing a desired degreeand characteristic of porosity is disclosed. The construct can include alaminated substrate including a plurality of independent layers ofmaterial placed adjacent one another and a plurality of pores formed inthe laminated substrate by the placement of a plurality of pore formingmembers in at least a selected one of the plurality of independentlayers of material prior to forming the laminated substrate. Theplurality of pore forming members are held in the selected plurality ofindependent layers of material until the laminated substrate is fullyformed and then destroyed in the laminated substrate to form the pores.

According to various embodiments, a construct for a structure includinga substantially selected porosity is disclosed. The construct caninclude a laminate preform including a plurality of layers of materialoperable to be processed into a laminated structure and a memberoperable to be positioned at least partially through the laminateperform, wherein the member includes a selected profile such that a poreleft in the laminated structure by the member allows a substantiallyuni-directional flow of a flowable material. The member is operable tobe destroyed from within the laminated structure to form a pore in thelaminated structure with at least one of substantially little oxidationand degradation to the laminated materials. The construct can alsoinclude a structure operable to be disposed adjacent to the laminatedstructure. The flowable material is operable to move through the pore inthe laminated structure to cool the structure.

According to various embodiments a construct including panel providing adesired degree and characteristic of porosity is disclosed. Theconstruct can include a substantially coherently laminated structureformed from a substantially oxide-free fabric stack and a pin operableto be placed into the fabric stack, the pin having a selected profilesuch that a selected pore remaining in the laminated structure allowsfor substantially uni-directional flow of a flowable material throughthe laminated structure. The pin is removed from the laminated structureto form the substantially selected pore in the laminated structure.

According to various embodiments a method of forming a laminated panelhaving a plurality of uni-directional pores is disclosed. The method caninclude forming a laminate preform including a plurality of layers ofmaterial and disposing a plurality of pore forming members in thelaminate preform in a selected pattern. The method can further includeprocessing the laminate preform to form a laminated structure andabolishing the pore-forming members in the laminated structure to form aplurality of uni-directional pores in the laminated structure.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and various examples areintended for purposes of illustration only and are not intended to limitthe scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present description will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a cross-sectional view of a laminate including pores accordingto an embodiment of the present invention;

FIG. 2 is an exploded view of the laminate and a pore forming apparatus;

FIG. 3 is an assembled view of a laminate and a pore forming apparatus;

FIG. 4A-4C is a pore forming apparatus according to various embodimentsof the present invention;

FIG. 5 is a flow chart for pore forming according to an embodiment; and

FIG. 6 is a flow chart for pore forming according to an alternativeembodiment.

DETAILED DESCRIPTION

The following description of various embodiments is merely exemplary innature and is in no way intended to limit the invention, itsapplication, or uses.

With reference to FIG. 1, a laminated structure 10 includes at least twolayers, a first layer 12 and a second layer 14 formed generally adjacentone another. In addition, an intermediate layer 16 may be formed orpositioned between the first and second layers 12, 14. The intermediatelayer 16 may be used for adhering the first and second layers 12, 14 toone another during a formation or laminating process. Nevertheless, itwill be understood that laminated layers may include a pre-impregnatedmaterial which can be used to affix the first and second layers 12, 14together during the formation process. Alternatively, the first andsecond layers 12, 14 may be fixed to one another, during the formationprocess, without any additional adhesive material. Also, it will beunderstood that the laminate structure 10 may include any number ofappropriate layers. Simply, the first layer 12 affixed to the secondlayer 14 is shown for clarity and is merely exemplary and not intendedto limit the scope of the present disclosure. Therefore, the laminatestructure 10 including any appropriate number greater than the twostructural layers 12, 14 and a single intermediate layer 16 may be used.

Formed through the laminate 10 is a plurality of bores or pores 20. Thepores 20 can be formed through the laminate 10 in any appropriate orselected manner. Generally, however the pores 20 are formed such that auniform density or porosity is formed in a selected area such as a firstset of pores 22. Moreover, the pores may be formed such that anon-porous area 24 is also formed. Furthermore, the pores 20 may beformed to include desired physical characteristics such as beinguni-directional. For example, uni-directional pores 26 allow the flow ofa flowable material from a first side 12 a to a second side 14 a. Afourth exemplary formed pore includes an angled pore 27 which is formedat a selected angle θ to a side of the laminate 10. This allows thematerial to flow to a selected area relative to the laminate 10. It willbe understood that the uni-directional pores 26 may also be formed suchthat material flows substantially only from the second side 14 a to thefirst side 12 a. In addition, due to the formation of theuni-directional pores 26, it may be that the uni-directional pores 26are positioned in any selected area of the laminate 10.

The first laminate layer 12 and the second laminate layer 14 maygenerally be formed of any appropriate material, for example non-oxidematerials. For example, the first layer may be formed substantially of acarbon reinforced silicon carbide material while the second layer 14 isformed substantially of a carbon reinforced carbon (Carbon-Carbon)material. Alternatively, both the first layer 12 and the second layer 14may be formed of a carbon fiber reinforced silicon carbide materialformed in an appropriate manner. Generally, the non-oxide first andsecond layers 12, 14 are formed to include selected physicalcharacteristics, such as strength or durability. In addition, the firstand second layers 12, 14 may be formed of a material that includes otherphysical characteristics such as thermal or electrical conductivity. Thenon-oxide materials may also be reinforced with carbon, silicon carbide,or other ceramic or metal fibers. Nevertheless, when the first andsecond layers 12, 14 are laminated together in the laminate 10, selectedphysical characteristics are found within the laminate 10. Moreover, thepores 20 formed in the laminate 10 are formed without destroying theselected physical characteristics of the laminate 10. Thus the laminatestructure 10 may include both selected physical properties and porosity.

If the first layer 12 and a second layer 14 were individually porousproviding the intermediate layer 16 may interrupt the continuousporosity from the first side 12 a to the second side 14 a. In addition,if the first layer 12 and the second layer 14 were inherently porous,the porosity may not be substantially continuous or uniform over theentire surface of the laminate 10. Therefore, the porosity would beunknown at various areas of the laminate material 10.

Therefore, forming the pores 20 through the laminate 10 as the laminate10 is formed substantially ensures that the porosity or the pores 20formed in laminate 10 are formed in a selected manner and according toselected requirements. Moreover, forming the pores 20 during themanufacturing of the laminate 10 ensures that the formation of the pores20 or the presence of the pores 20 does not destroy the selectedphysical or chemical characteristics of the laminate 10.

With reference to FIG. 2, the pores 20 (illustrated in FIG. 1) may beformed using a pore forming apparatus 30. The pore forming apparatus 30generally includes a base 32 and a plurality of pins or pore formingmembers 34 extending from the base 32. Generally, the pins 34 include asubstantially sharpened top or engaging end 36 that is used to pierce aportion of a laminate preform 40. The laminate preform 40 includes eachof the layers which will eventually form the laminate structure 10, butwhich have not yet been laminated (in other words, the process to makeeach of the layers 12, 14 substantially coherent has not yet occurred).The layer 12, 14 of the laminate preform 40 may also include reinforcingfibers F, F′. The reinforcing fibers F, F′ may be any appropriatematerial to provide selected properties to the layers 12, 14. Thereinforcing fibers F′ in the first layer 12 may be the same or differentthan the fibers F′ in the second layer. The pins 34 pierce the laminatepreform 40 to form desired pores in the laminate preform 40 which willbecome the pores 20 once the pins 34 are removed.

The pins 34 are also able to move the fibers F, F′ during the insertionof the pins 34. Therefore, the pins 74 do not destroy the fibers F, F′nor the properties they impart to the laminate 10, once formed.

With continued reference to FIG. 2 and additional reference to FIG. 3,the laminate preform 40 is pressed onto the pins 34 to a selected depthor distance. During this process, the sharpened ends 36 and the pins 34are able to move the fibers F, F′ rather than break them. In theunprocessed state, the fibers F, F′ are able to move within the layers12, 14 rather than breaking. Generally, the pins 34 include a heightselected to provide a desired pore depth into the laminate structure 10.Generally, pores are formed through laminate structure 10 such that aflowable material is able to pass from the first side 12 a to the secondside 14 a. The pore forming apparatus 30 can be pressed through thelaminate preform 40 or the laminate preform 40 pressed onto the poreforming apparatus 30. Nevertheless, the pins 34 engage and typicallypass through each of the layers of the laminate preform 40 to formregions that become the pores 20 in the laminate structure 10.

The pins 34 may be formed or placed on the base 32 of the pore formingapparatus 30 in any appropriate shape or pattern. Moreover, the pinforming apparatus 30 may be shaped to any appropriate geometry. In thisway as the laminate preform 40 is placed over the pore forming apparatus30, it conforms to the shape of the pore forming apparatus 30 such thata complimentary shape or a similar shape is formed in the laminatepreform 40 as the pores 20 are formed in the laminate preform 40.

Because the pins 34 may be positioned on the base 32 in any appropriateconfiguration or pattern, selected porosities or designs of porositiescan be formed in the laminate 10. In addition, each of the pins 34positioned on the base 32 may be of a selected size or geometry.Therefore, a first set of the pins 34 may be a first size, while asecond set is a different size. Moreover, the pins 34 may include auni-directional pore shape, such that the flowable material passes onlyin one direction, and again only some of the pins placed on the base 32may include this attribute while others do not. Moreover, the pins 34may pierce at some selected angle so as to create pores at the selectedangle θ.

With reference to FIG. 4A to 4C, exemplary pore forming geometries areillustrated. With particular reference to FIG. 4A, the pore formingapparatus 30 a includes a plurality of the pins 34 formed in a pluralityof rows 42 _(1 to) 42 _(n). An opening 44 is left in the pattern suchthat pores will not be formed in a selected area of the laminate 10. Theopen area 44 may be any appropriate shape or size and may used forforming an opening or hole in the laminate 10. Particularly, if there isan opening for a rod or tube, no pores would be formed therein.

With particular reference to FIG. 4B, the pore forming apparatus 30Bincludes a first set of pins 46 having a first diameter X and a secondset of pins 48 having a second diameter Y. The first diameter X may beany diameter different than the diameter Y. Therefore, the laminate 10will have pores formed therein that include pores of various sizes. Thismay be desirable especially if the laminate 10 is to be used to cover toadjacent sections requiring a different size pore in each section. Thistechnique may also be used to vary the rate of material transport acrossdifferent portions of the laminate 10.

With particular reference to FIG. 4C, a pore forming apparatus 30 cincludes a first section of pins 50 and a second section of pins 52. Thefirst section pins 50 may be formed in a particular pattern, such as atriangle for forming pores in the laminate 10 in the selected pattern.Moreover, the pins in the first section 50 include a first density whichis different than the density of the pins in the second section 52.Furthermore, the shape or general pattern of the second set of pins 52may differ from the first set of pins 50. Therefore, several differentpore forming apparatuses can be produced to provide various differentporosities, pore sizes, pore shapes or pore patterns. In this way, thelaminate 10 may include a porosity of any selected manner.

With reference to FIG. 5, a flow chart of a method 60 for forming theporosity in laminate 10 is illustrated. The method 60 begins at step 62.After the process has started, a fabric stack or a fabric preform isformed in step 64. That is, that the first layer 12 and the second layer14 of the laminate preform 40, before being laminated into a finallaminate structure 10, are formed into the desired shape or size forbeing laminated. The first and second layers 12, 14 may be formed into ashape and size at the perform stage for which is required for the finallaminate structure 10.

After the stack fabric perform is formed in step 64, the pin can beinserted in step 66. For example, glass or molybdenum pins can beinserted at step 66 into the fabric preform. It will be understood thatthe pins may be inserted into the preform, formed in step 64, accordingto any selected size, porosity, or shape, as discussed above.

After the pins are inserted into the fabric preform at step 66, thefabric preform may be tooled or worked at step 68. It will be understoodthat such tooling may not be desirable in the preform stage; thereforetooling is not necessary for carrying out the method 60. Nevertheless,certain tooling may be used to further modify the preform to achieve adesired shape or size. After the selected tooling is used or directlyafter the glass pins are inserted in block 66, an interfacial coating isdeposited upon the fiber preform utilizing chemical vapor deposition orpolymer pyrolisis in step 70.

After the pins have been inserted in step 66 and the interfacial coatingis applied in step 70, the preform is infiltrated in Block 72 with amatrix material for example a silicon carbide ceramic via a polymerinfiltration and pyrolysis (PIP), liquid metal melt infiltration (MI),or chemical vapor deposition (CVD) process. The preform is infiltratedwith the material to allow lamination of each of the layers in thepreform. After the preform is infiltrated, a check for an appropriatedensity is done at step 74. If the material is not found to have aselected density, further infiltration is done of the preform in step72.

Once the selected density is reached of the infiltrated preform, thepins may be etched out in step 76. The pins may be removed by destroyingor abolishing the pins, such as by etching out in step 76 according toany appropriate manner. It will be understood the pins are generallydestroyed during removal such that they are unusable yet the processleaves intact selected properties of the laminate. For example, the pinsmay be generally etched out by chemical etching of the pins from thelaminate structure 10. That is, that the glass or metal forming the pinsthat were placed in the preform are etched out with a chemical that doesnot react with the laminate materials, but only with the glass pins.Therefore, it will be understood, that the pins are inserted into thepreform in step 64 and remain in place until after the laminatestructure has been laminated or infiltrated in step 72. Thus, the pinsinserted in step 66 are not removed from the preform structure untilafter the laminate structure is completely formed.

After the glass pins are etched out in step 76, the laminate is finishedin step 78. The laminate finishing 78 may include any appropriate stepssuch as inspection, machining, and cleaning. Moreover, testing of thephysical properties of the laminate may be done in the finishing step instep 78. If initial tooling was not done, or if initial tooling is done,final tooling of the laminate structure may be desirable in thefinishing step 78 to provide for the selected structure shape or size.

With reference to FIG. 6, a second exemplary method to form the laminate10 is illustrated according to a flow diagram 90. The second method 90begins at start block 92. After the start block 92, a stack fabricpreform is formed in step 94. The fabric preform may be formedsubstantially similar to the fabric preform 64 according to the method60. Polymer pins are inserted at step 96 into the fabric preform formedat step 94. After the stack fabric preform is pinned at step 96, thepreform may be tooled at step 98. The pinned preform, tooled oruntooled, is then infiltrated at step 102 for lamination of the layers.Alternatively, for a ceramic laminated material, this process utilizes apolymer ceramic precursor which is solidified through a cure or dryingprocess, which is pyrolized at step 102 to convert it into the desiredceramic. In one example, this may be the process to form silicon carbidearound carbon fibers.

After the polymer pins are inserted into the fabric preform, the fabricpreform is infiltrated with a selected polymer ceramic precursor ormaterial at step 102. The infiltration allows for the laminate structureto form between the various layers of the stack fabric preform. Theinfiltration of the preform at step 102 substantially provides thedensity required for the laminate structure. Although a checking processor step may follow the infiltration of the preform after step 102, theinfiltration process is not generally repeated according to the method90.

After the fabric preform has been infiltrated at step 102 and rigidized(i.e. cured), the polymer pins may be melted out at step 104. Morespecifically, the laminated structure, including the polymer pinsinserted therein, which was inserted into the preform at step 100, aredestroyed or abolished. For example, the pins may be melted during thecuring step. Generally the temperature required to melt out the polymerpins at step 104 is a temperature below that which substantiallydisrupts the structure of the laminate structure. Rather than injuringthe structure of the laminate structure formed after the infiltration atstep 102, the pins are simply melted out at step 104. This allows asubstantially porous structure according to any selected design.

After the polymer pins are melted out of the laminate structure thepolymeric infiltrant is pyrolized according to the prescribed PIPprocess and converted into a ceramic in Step 102. It will be understoodthat PIP step 102 may occur at any appropriate time. The laminate isthen finished in step 106. Similar to the laminate finish at step 78,various steps may be performed to finish the laminate at step 106. Forexample, the laminate structure may be examined for the desired physicaland chemical properties, structure machined and cleaned. Furthermore,permeability testing of the laminate structure may occur to ensure thatthe selected permeability properties have been formed by the placementof the polymer pins into the preform in block 100.

Generally, the materials for forming the laminate structure 10 aresubstantially non-oxide materials. Moreover, the materials forming thelaminate structure 10 may be disrupted by oxidation of the materials inthe various layers. Therefore, removing the pins, through anyappropriate method, does not substantially oxidize the material of thelaminate structure 10. To that end the pins may be selected of amaterial that may be removed using processes which do not substantiallyoxidizing the layers of the laminate 10.

Moreover, the materials forming the layers 12, 14 of the laminatestructure 10 allow for a substantially strong laminate. The placement ofthe pins 34 allow for the laminate structure 10 to be selectivelyporous. Therefore, a high strength laminate structure 10 or panel can beprovided with a desired degree of porosity. The laminate preform 40includes a plurality of independent layers of material placed adjacentone another. Then, as described above, a plurality of pores are formedin the laminate structure 10 by placing the pins 34 in the laminatepreform 40. The plurality of pore forming members 34 are held in aselected plurality of independent layers of material until saidlaminated structure 10 is fully formed. Then the pins 34 are removedfrom the laminated substrate to form the pores 20.

For example, the pins may be formed from a polymer material of aselected diameter or density to penetrate the preform which can then bemelt or burnt out during a pyrolysis cycle. Alternatively, a glass ormetallic fiber may be used that can be etched out substantially easilyfollowing one or several infiltration cycles as determined by theparticular infiltration method prescribed. Although it will beunderstood that these are merely exemplary in nature and any appropriatematerials for forming the pins 34 for the pore forming structure 30 maybe used.

In addition, the materials for forming pins 34 generally do not interactwith the infiltration for formation of the laminate structure. Morespecifically, that the pins remain in place during the formation of thelaminate but are easily removed afterwards to leave the desired porosityor pore size in the laminate structure 10. Therefore the pins do notgenerally interact with the infiltration material and generally onlysublime or burn out when selected. Nevertheless, pins are provided thatcan be pressed through the preform laminate material withoutsubstantially deforming or substantially damaging reinforcementsdisposed in the laminate layers.

The laminate structure 10 may be used for any appropriate use. Exemplaryuses are described in U.S. Pat. No. 7,128,532, issued Oct. 31, 2006,entitled, “A TRANSPIRATION COOLING SYSTEM” to Miklos Petervary, andcommonly assigned, incorporated herein by reference. For example thelaminate structure 10 including the pores 20 may be used fortranspiration cooling of a structure. In a further example, the laminatestructure 10 may be used as the hot wall of a combustion chamber where aflowable cooling material that is flowed on the backside could then flowthrough the pores 20 at a selected rate to cool the hot wall surface.The laminate structure 10, however, includes the selected porosity sothat the selected flow rate occurs. Moreover, the substantiallyconsistent porosity assures that the porosity is present in the laminatestructure 10 at the selected area thus providing uniform transpirationand therefore uniform cooling.

The description is merely exemplary in nature and, thus, variations thatdo not depart from the basic premise of the description are intended tobe within the scope of the description. Such variations are not to beregarded as a departure from the spirit and scope of the description.

1. A construct for a structure that has a selected porosity, comprising:a laminate preform including a plurality of layers of non-oxide materialoperable to be processed into a laminated structure wherein thelaminated structure includes the selected porosity; a member formed ofglass to be positioned at least partially through said laminate preformwithout disrupting a reinforcing fiber in the non-oxide material toallow formation of the selected porosity, wherein the member includes aprofile having a first dimension at a first end and a second dimensionlesser than the first dimension at a second end such that a pore left insaid laminated structure by said member has a third dimension equivalentto said first dimension at a first end near a first side of saidlaminated structure and a fourth dimension equivalent to said seconddimension at a second end at a second side of said laminated structureand allows a substantially uni-directional flow of a flowable material;wherein the member is removed from within said laminated structure onlyafter curing of said laminate preform to form the laminated structureand to form the selected porosity in said laminated structure withsubstantially little oxidation or degradation to the laminatedstructure; wherein a structure is operable to be disposed adjacent tosaid laminated structure, wherein the flowable material is operable tomove through the selected porosity in the laminated structure to coolsaid structure.
 2. The construct of claim 1, wherein the member includesa plurality of members operable to provide the selected porosity in saidlaminated structure when the plurality of members are removed from saidlaminated structure to form the selected porosity in the laminatedstructure.
 3. The construct of claim 2, wherein the member has at leastone of a selected size, shape, dimension, and property; wherein themember has a side that tapers from said first end to said second end andwill form an angle relative to a side of the laminate preform.
 4. Aconstruct including panel providing a selected porosity, comprising: asubstantially coherently laminated structure formed from a substantiallyoxide-free fabric stack; and a plurality of molybdenum pins placed intothe fabric stack, each molybdenum pin of the plurality of molybdenumpins having a profile that is wider at a first end of the pin than at asecond end of the pin such that a selected pore remaining in thelaminated structure is wider at a first end than at a second end andallows for substantially uni-directional flow of a flowable materialthrough the laminated structure; wherein the molybdenum pin is removedfrom the laminated structure to form the selected porosity in thelaminated structure after the laminated structure is formed from thesubstantially oxide-free fabric stack; wherein said fabric stackincludes a first layer of the fabric and a second layer of the fabricpositioned in a selected orientation for forming the laminatedstructure; wherein the plurality of molybdenum pins are positionedthrough each of the first layer of the fabric and the second layer ofthe fabric stack without substantially disrupting the selectedorientation of each of said layers or reinforcing fibers in the firstlayer of the fabric or the second layer of the fabric; wherein theplurality of pins forms a plurality of pores that define a porous fielddefining an area of pores in the laminated structure; wherein thelaminated structure further defines a non-porous field having no poresformed by the plurality of molybdenum pins.
 5. The construct of claim 4,further comprising: a coolable structure to be cooled; wherein thesubstantially coherently laminated structure is positioned a selecteddistance from the coolable structure; wherein the flowable material isoperable to flow in a uni-directional flow through said laminatedstructure to cool the coolable structure.
 6. The construct of claim 4,wherein the substantially oxide-free fabric includes carbon reinforcedsilicon carbide material and/or carbon reinforced carbon(Carbon-Carbon).
 7. The construct of claim 4, wherein the molybdenum pinis to having one of a plurality of external widths such that a firstpore includes a first internal dimension and a second pore includes asecond internal dimension; wherein the first internal dimension and thesecond internal dimension are different; wherein the first pore and thesecond pore are both within the porous field.
 8. The construct of claim4, wherein the laminated perform is operable to be positioned adjacent apore forming apparatus including having a base; wherein the molybdenumpin includes a plurality of molybdenum pins each positioned to extendfrom the base; wherein at least one of the plurality of the molybdenumpins includes a substantially sharpened engaging end that is used topierce a portion of the fabric stack.
 9. The construct of claim 4,wherein the pore includes an angled pore having a side formed at aselected angle to a side of the laminate structure; wherein the selectedangle is selected to allow a flow in only one direction through thelaminated structure.
 10. The construct of claim 9, wherein the angle ofthe pore relative to a side of the laminated structure is substantiallyidentical to an angle of the molybdenum pin.
 11. A member having aselected degree and characteristic of porosity, comprising: a laminatedmember that is formed by curing a pre-formed laminate of a plurality ofindependent layers of material placed adjacent one another; a pluralityof pores formed in said laminated member by a placement and subsequentremoval of a plurality of pore forming members, wherein the pore formingmembers are placed in at least a selected one of said plurality ofindependent layers of material prior to forming said laminated memberand the pore forming members are removed from the at least a selectedone of said plurality of independent layers of material subsequent toforming said laminated member; and wherein the plurality of pore formingmembers are held in said at least one selected of said plurality ofindependent layers of material until said laminated structure is fullyformed and wherein the then the plurality of pore forming members aredestroyed from within said laminated member to form said plurality ofpores; wherein the material of each of the plurality of independentlayers is formed of a substantially oxide-free fabric including at leastreinforcing polymeric fibrous materials; wherein the pore formingmembers are formed of at least one of molybdenum or glass.
 12. Themember of claim 11, wherein the plurality of pore forming members aredestroyed by chemically etching the pore forming member from thelaminated member; wherein the plurality of pore forming members aredestroyed with at least one of substantially little oxidation ordegradation to the laminated member.
 13. The member of claim 11, whereinthe plurality of pore forming members are destroyed by at least one ofsublimation or melting; wherein the plurality of pore forming membersare destroyed with at least one of substantially little oxidation ordegradation to the laminated member.
 14. The member of claim 11, whereinthe plurality of pore forming members are formed of glass and positionedin at least two of the independent layers, wherein the pore formingmember formed of glass is destroyed to form substantially continuouspores through the at least two layers of the laminated member.
 15. Themember of claim 14, wherein the laminated structure is operable to beshaped on a tool operable to shape the independent layers.
 16. Themember of claim 14, further comprising: at least a sub-plurality of theplurality of pores in said laminated structure having a first dimensionat a first end near a first side of said laminated structure and asecond dimension at a second end at a second side of said laminatedstructure to allow the uni-directional flow; wherein the laminatedstructure including the plurality of pores is operable to be placed neara coolable structure to be cooled; wherein the laminated structure issubstantially coherently laminated; wherein the substantially coherentlylaminated structure is positioned a selected distance from the coolablestructure; wherein a flowable material is operable to flow in auni-directional flow through said laminated structure to cool thecoolable structure.
 17. The member of claim 14, wherein the pore formingmembers are operable to be selected of a plurality of external widthssuch that a first pore includes a first internal dimension and a secondpore includes a second internal dimension; wherein the first internaldimension and the second internal dimension are different.
 18. Themember of claim 14, wherein the plurality of pores define a field ofsubstantially porous area in the laminated structure; wherein an areawithin the fields includes substantially no pores formed by the poreforming members.
 19. The member of claim 14, wherein the plurality ofpores define a field of substantially porous area in the laminatedstructure; wherein a first portion of the field includes a first densityof pores and a second portion of the field includes a second differentdensity of pores.
 20. The member of claim 14, further comprising: abase; wherein each of the plurality of the pore forming members extendsfrom the base; wherein at least one of the pore forming members includesa substantially sharpened engaging end that is used to pierce a portionof the plurality of independent layers of material prior to thelaminated member being cured.
 21. The member of claim 12, wherein theplurality of the pore forming members are formed of molybdenum andcapable of surviving final processing of the independent layers into thelaminated member and thereafter being destroyed, and wherein theplurality of the pore forming members are positioned in at least two ofthe independent layers to form substantially continuous pores through atleast two layers of the laminated member.
 22. The construct of claim 21,wherein the plurality of independent layers of material are selectedfrom a group consisting of carbon reinforced silicon carbide materialand/or carbon reinforced carbon (Carbon-Carbon).